Effect of pyrolysis temperature on chemical form, behavior and environmental risk of Zn, Pb and Cd in biochar produced from phytoremediation residue. (February 2018)

• Record Type: Journal Article
• Authors: Huang, Hui; Yao, Wenlin; Li, Ronghua; Ali, Amjad; Du, Juan; Guo, Di; Xiao, Ran; Guo, Zhanyu; Zhang, Zengqiang; Awasthi, Mukesh Kumar
• Is Part Of: Bioresource technology. Volume 249(2018)
• Page Start: 487
• Page End: 493
• Publication Date: 2018-02
• Subjects: Phytoremediation residue -- Biochar -- Ecotoxicity -- Heavy metals -- Risk evaluation; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2017.10.020
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: Zn, Pb and Cd laden biochars from phytoremediation residue were prepared. Effects of pyrolysis on biochar physicochemical properties were investigated. Variation in chemical form and behavior of Zn, Pb and Cd in biochar were tested. Pyrolysis treatment alleviates the Zn, Pb and Cd bioavailability in biochar. Temperature above 550 °C resulted biochars were with acceptable environment risk. Abstract: This study aimed to evaluate the chemical forms, behavior and environmental risk of heavy metal (HMs) Zn, Pb and Cd in phytoremediation residue (PMR) pyrolyzed at 350 °C, 550 °C and 750 °C, respectively. The behavior of HMs variation during the PMR pyrolysis process was analyzed and the potential HMs environmental risk of phytoremediation residue biochars (PMB) was assessed which was seldom investigated before. The results showed that the pyrolysis temperature increase decreased the soluble/exchangeable HMs fraction and alleviated the HMs bioavailability. When the temperature was over 550 °C, the adsorbed Zn(II), Pb(II) and Cd(II) were turned into oxides forms and concentrated in PMB with more stable forms exhibiting lower risk assessment code and potential ecological risk index. The ecotoxicity test showed higher pyrolysis temperature favored the reduction of PMB ecotoxicity. It is suggested that pyrolysis temperature above 550 °C may be suitable for thermal treatment of PMR with acceptable environmental risk.